The present invention relates to a wheel knob for an industrial vehicle and an industrial vehicle.
Conventionally, a steering wheel knob is formed on the steering wheel of a forklift, such as a reach type so that steering can be done with one hand. There may be a case where switches mounted on an instrument panel are operated while doing a steering operation depending on the circumstance. At this time, one needs to temporarily set the hand off the steering wheel knob in order to operate the switches on the instrument panel, thus raising a problem that the workability drops.
To solve the problem, the present applicant has proposed a steering wheel 200 as shown in FIG. 35 provided with a switch thereon in Japanese Unexamined Patent Publication No. Hei 9-215116. The steering wheel knob 200 is provided with a creep drive switch 201 and when the creep drive switch 201 is depressed, its detection signal is output to a control circuit 202. Then, when receiving the detection signal from the switch 201, the control circuit 202 controls a three-phase power converter 203 and drives a drive motor 204 to cause a vehicle to drive in creep mode.
Japanese Unexamined Patent Publication No. 2000-72000 discloses a steering wheel which can permit a switch operation while a steering wheel knob is being held. This steering wheel 206 is a steering wheel for handicapped persons and a grip holder 207 is attached to the steering wheel 206. Attached to the grip holder 207 are a grip (steering wheel knob) 208 and a switch case 212 which has three switches 209 to 211 for a horn, winker and light. The various switches 209 to 211 are operated by stretching a finger while holding the grip 208, which can ensure a steering operation and a switch operation simultaneously.
Although not described in Japanese Unexamined Patent Publication No. Hei 9-215116, it appears that the creep drive switch 201 is connected to the control circuit 202 by a wire. While the switch is provided on the steering wheel knob 200, therefore, the wires (harnesses) that connect the switch 201 to the control circuit 202 may suffer frictional wear or interfere when the steering wheel is operated, thereby raising a problem of disconnecting the line. In case where the steering wheel knob 200 is made movable relatively to a steering wheel 205, the problem becomes particularly noticeable.
Japanese Unexamined Patent Publication No. 2000-72000 describes that the switches 209 to 211 are connectable to the electric circuitry (not shown) for control wirelessly. While the switches 209 to 211 are radio-communicatable and the grip 208 and the switches 209 to 211 can be operated at the same time, however, fingers should be let go of the grip 208 at the time of the switch operation, the hold on the grip 208 would become loose, making the steering operation unstable.